Method and apparatus for smoothing the output of a hydrostatic transmission near zero speed
US6343250B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 19, 2000 |
| Grant date | Jan 29, 2002 |
| Priority date | — |
| Expiry date | May 19, 2020 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2037/0886
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A transmission assembly includes a variable displacement hydraulic pump, a hydraulic motor operatively connected to the pump, a speed sensor operable to sense the speed of an output shaft of the motor, a first actuator for setting displacement of the pump in a positive displacement range in response to a first actuator command and a second actuator for setting displacement of the pump in a negative displacement range in response to a second actuator command. A controller is operable to transmit first actuator commands to the first actuator and transmit second actuator commands to the second actuator in response to operator inputs. The operator inputs require that the displacement of the pump to move from the positive displacement range to the negative displacement range. The controller generates first actuator commands which cause the first actuator to set the displacement to zero. The controller generates second actuator commands in response to the speed of the output shaft reaching a predetermined motor speed limit which cause the second actuator to set the displacement of the pump in the negative displacement region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.